The Sigil-Ridden Navigator
From The Fifth City Wiki
The Sigil-Ridden Navigator made a mistake on his last ship. The captain drove them to King eater's castle, and then, due to lack of supplies, farther east in hope of land. Eventually they were forced to return, and the Sigil-Ridden Navigator mislaid their course. With dwindling supplies they were forced to cannibalism, there were seven victims. When they returned to london, one of the cannibals confessed, and he fled the noose.
In the Avid-Horizon he begged to return, willing to sacrifice anything. He was refused. In desperation he ran to the Chapel of Lights, and had a sigil engraved on him, so he would no longer remember his sins.